time consuming to calculate result value by value in a array or table

[francispau]

Hello!

I input data from a text file to a table in labview,  so i have 3 table .

i do some calculations  in labview and i have finaly one table .

The problem : i have 3 tables of 26000 lines..., so to calculate the result  and to input value by value in an labview table it consume a lot of time .

With excel it's very fast to calculate the new column, but in labvie i don't know how to do...

Any examples would be greatly appreciated.

Thank you

i use labview 7.0

[becktho]

Hi

Could you post the vi? It's easier for the community to give good advice, if we can see what you've done so far.

Thomas

[francispau]

Ok , i give you a example

thank you very much

[becktho]

Two things about your vi:

1. Once you write "SI(AX<A(X+1()" but it is just "Bn > Ai and you also write "SI(A(X+1)<A(X+1))=> CX" but it is just Ai > B(n+2). What is correct - the wires or the commented formulas?

2. You insert élément 2 in the listbox - which value do you want to write? The value which is returned after in the inner case structure?

[Elsa Fung]

1. You might want to use auto indexing for A (just to simplify the code), I'm not sure if it'll improve preformance or not, who knows what LabVIEW does underneath ^_^

2. it doesn't seem like Numérique is changed during the run, you might want to pull the Index Array of B out of the loop so it's not repeatedly run (is it suppose to change? the index for B??)

3. There is no need for the Selector when comparing B < A, you're basically saying "if B < A is true, send true, if it is false, send false"

4. You might want to consider wiring élément 2 from the case select to replace array directly instead of going thru setting the value of élément 2.  This is because LabVIEW doesn't really run codes in any other, so when your program's still trying to figure out which value to write to élément 2, the replace array block might have been executed already.  élément 2 is actually not needed at all.

5. You might want to move Résultat out of the loop unless you need to observe the values changing in Résultat when the loop is running.  This should help reduces the run time a little.

Hope this helps ^_^

Message Edited by Elsa Fung on 01-09-2006 08:12 AM

[IanW]

If you take the string array indicator outside of the loop and connect to the right hand shift register you should see a big improvement in speed. It would also help to do away with the local variables and wire directly.

Ian

[becktho]

Here is an updated version of your vi, with some improvement suggested from the others.

What brought a major speed boost, was the removal of the local variables of the arrays.

Depending on the logic (comparison of different indexes) there still may be some potential for improvement left.

Thomas

[francispau]

THANK YOU , THANK YOU VERY MUCH,

[francispau]

THANK YOU , THANK YOU VERY MUCH, i

[francispau]

THANK YOU , THANK YOU VERY MUCH, i will